Lab Monitoring
Reference
Understanding Lab Results on GLP-1: Normal Ranges
A patient-friendly guide to reading your blood work -- what each number means and what to expect on GLP-1 medication.
Last updated: April 1, 2026-14 min read
Lab results can feel like a foreign language. But understanding your numbers empowers you to track your progress, ask better questions, and appreciate the metabolic transformation happening inside your body on GLP-1 medication. Here is your complete reference guide.
Metabolic Panel
Blood Sugar and Metabolic Tests
| Test | Normal Range | GLP-1 Effect | Concern If |
|---|---|---|---|
| Fasting glucose | 70-99 mg/dL | Decreases | Below 60 or above 126 |
| HbA1c | Below 5.7% | Decreases 0.5-2% | Rising or above 6.5% |
| Creatinine | 0.6-1.2 mg/dL | Usually stable | Rising trend |
| eGFR | Above 60 mL/min | Usually stable or improves | Below 30 |
| Sodium | 136-145 mEq/L | Usually stable | Outside range |
| Potassium | 3.5-5.0 mEq/L | Usually stable | Below 3.5 or above 5.5 |
Lipid Panel
| Test | Optimal | Borderline | GLP-1 Effect |
|---|---|---|---|
| Total cholesterol | Below 200 | 200-239 | Decreases |
| LDL | Below 100 | 100-159 | 15-25% decrease |
| HDL | Above 60 | 40-59 | 5-10% increase |
| Triglycerides | Below 150 | 150-199 | 25-40% decrease |
Liver Function
| Test | Normal | GLP-1 Effect | Notes |
|---|---|---|---|
| ALT | 7-40 U/L | Often normalizes | Fatty liver marker |
| AST | 8-40 U/L | Often normalizes | Liver/muscle marker |
| ALP | 44-147 U/L | Usually stable | Bile duct marker |
Thyroid and Other Tests
| Test | Normal | Notes |
|---|---|---|
| TSH | 0.4-4.0 mIU/L | Monitor for thyroid changes; adjust levothyroxine if needed |
| Vitamin D | 30-80 ng/mL | Supplement if below 30; many patients deficient |
| Vitamin B12 | 200-900 pg/mL | Supplement if below 400 (especially with metformin) |
| hs-CRP | Below 1.0 mg/L (low risk) | Dramatic decrease on GLP-1 |
| Hemoglobin | 12-16 g/dL (women), 14-18 (men) | Monitor for anemia with reduced intake |
Tips for Reading Your Results
- Track trends: A single result matters less than the direction over time
- Compare to YOUR baseline: Your starting point is your most important reference
- In-range is not always optimal: A CRP of 3.0 is "normal" but not ideal
- Ask your provider: If anything is outside range, discuss rather than worry alone
- Keep copies: Maintain your own record of all lab results for comparison
Know Your Numbers
Trimi physicians help you understand and improve your lab results. Semaglutide $99/mo. Tirzepatide $125/mo.
Get StartedMedical Disclaimer
Normal ranges may vary by laboratory. This reference is for general education. Always discuss your specific results with your healthcare provider. Do not make treatment decisions based on this article alone.
More on GLP-1 lab monitoring
Sources & References
- Wilding JPH et al. Once-Weekly Semaglutide in Adults with Overweight or Obesity. NEJM 2021;384:989-1002.
- Jastreboff AM et al. Tirzepatide Once Weekly for the Treatment of Obesity. NEJM 2022;387:205-216.
- Lincoff AM et al. Semaglutide and Cardiovascular Outcomes in Obesity without Diabetes. NEJM 2023;389:2221-2232.
- FDA Prescribing Information for Wegovy (semaglutide) and Zepbound (tirzepatide).